[Not Applicable]
[Not Applicable]
1. Field of the Invention
This invention provides for an integrated device having a lance and analytic device in a single disposable unit where the lance releases fluid from skin and the analytic device collects and analyzes the fluid without the user removing an instrument housing which holds the disposable unit. In addition to the device, this invention provides for methods of using and manufacturing the device.
2. Description of Prior Art
The art of body fluid sampling is inundated with a wide variety of sampling methods and instruments. By traditional methods, in order to perform analysis on biological fluid, a patient is required to make a trip to their physician""s office and donate a sample. This is usually in the form of a blood or urine sample that is subsequently delivered to a laboratory and eventually analyzed. In order to obtain the blood sample, it is most common for a hypodermic to be inserted into a vein to gather a large volume of blood, the majority of which is not used in most cases. More recently, blood tests and analyzers have been developed which require the pricking of a finger to supply a drop of blood, which is analyzed by a separate unit.
In recent years there has been a growing need to provide the ability to perform body fluid analysis on the spot, without sending an individual to a physicians office, and a fluid sample to a lab for analysis. Law enforcement and military have pressing needs to be able to perform on the spot testing for drugs of abuse and exposure to CBR (chemical biological and radiological) warfare. Furthermore, in order to enhance the quality of life and for proper management of health, there has been a push to equip the common individual to perform biological fluid testing at home or during normal day-to-day routines without having to visit their physician. Several types of instruments have been developed along the lines of home pregnancy testers, hemoglobin testers, and blood glucose testers for diabetics.
Diabetes mellitus is a chronic disease that affects more than 15 million Americans. About seventy five percent of these are type 2 (non-insulin dependent). Accurate blood glucose monitoring is required for proper management of blood sugar levels for diabetics. Several systems have been developed over the recent years permitting home testing of blood sugar levels. Most of these systems require the user to draw a blood sample usually from the fingertip and deliver the blood sample to a collection device in the form of a capillary and reservoir with predisposed reagents for analysis. Due the sensitivity of the fingertips however, testing is quite painful and even traumatic for many users, especially among children and infants. Recently devices have been developed which sample body fluid from the forearm as a means of drawing body fluid painlessly, U.S. Pat. Nos. D0427312, 06,120,676, D0426,638, D0424,696. However, obtaining the volume of blood required for these systems from the forearm has been difficult.
The art of body fluid sampling is inundated with a variety of instruments and sampling devices, available in a large range of designs. Integration of the skin-penetrating member with the fluid collecting and analyzing portion of body fluid analyzers is uncommon in the industry. Most body fluid analyzing instruments come in two different parts: a skin penetrating instrument, and a collection and analysis instrument. This is a prevalent shortcoming of the current art, the methods and instruments designed for body fluid sampling require two distinctly different steps: a lancing step and a filling step, which requires manual delivery of a relatively large volume of body fluid to the collection device. The proper delivery of the blood to the collection device often requires a good deal of dexterity and is quite difficult for older diabetics, and individuals with failing eyesight. Often the blood drop ends up smeared along the test collection device or on the user, creating a mess and a failed test. As a result tests often need to be repeated several times until the procedure is performed properly.
A device that integrates the skin penetrating and fluid collecting procedures has many advantages. Integrated systems do not require as large as a volume of body fluid to be produced as required for non-integrated systems. This is because integrated systems may be used in a more automated system, eliminating the patient as the fluid delivery mechanism. Integrated and automated systems may demonstrate a high level of precision in collecting the sample, allowing for smaller sample sizes to be generated. Smaller sample sizes result in smaller lancet sizes, less pain and trauma for the user, and fewer if any failed tests.
Several companies and individuals have developed various devices in an attempt to integrate the sample production and collection devices and automate the process. However, there are few, if any, truly integrated skin penetrating and collecting devices currently available.
One such device described by Smart and Subramanian, U.S. Pat. No. 5,801,057, refers to a silicon microsampler. The silicon microsampler is a microchamber forming a cuvette with an integrated hollow silicon needle. The microchamber and needle are formed from one silicon substrate through a series of etching processes. The microchamber and microneedle of the microsampler are covered with a glass layer that is anodically bonded to the silicon portion. The microsampler is filled by inserting the microneedle into the skin; under the skin surface, the microneedle contacts a blood sample and draws it into the microcuvette for analysis.
U.S. Pat. No. 4,873,993, Cuvette, assigned to Personal Diagnostics Inc., describes xe2x80x9ca cuvette with or without a lancet secured thereto and extending therefrom for producing skin puncture to produce body fluid of interest, the cuvette is made of optically transparent material and is provided with a shape and a plurality of optical elements such as integrally formed optical elements for causing a light beam to pass therethrough by total internal reflectance and for causing the beam of light to be reflected back along a line different from the direction of the line of entry of the beam of light into the cuvette such as back along a line generally parallel to the line of entry of the beam of light into the cuvette and in the opposite direction to the direction of entry of the beam of light into the cuvette.xe2x80x9d This device is used with an instrument that performs the lancing operation, U.S. Pat. No. 5,029,583. However, the lance and cuvette are not attached in such a way to facilitate automated filling of the cuvette. The cuvette filled manually by the patient xe2x80x9cwipingxe2x80x9d the body fluid sample across the opening to the cuvette.
Another device described by Garcia et al., U.S. Pat. No. 4,637,403, refers to a hand-held portable medical diagnostic device. The system utilizes a xe2x80x9cdisposable needle or lance probe package which carries a chemical reagent strip.xe2x80x9d The disposable is used within an instrument utilizing xe2x80x9ca spring arrangement for actuating a needle or lance into the skin for transferring blood from a finger or other area to the chemical reagent strip.xe2x80x9d The instrument and actuation system may also create a vacuum at the lance site to help move blood from the wound to the test strip.
Another application described by Douglas et al., U.S. Pat. No. 6,099,484, refers to methods and apparatus for sampling and analyzing body fluid. The device described is an instrument containing a lancet for making an incision, a capillary tube for drawing up fluid, and a test strip affixed to the capillary tube. Various embodiments of the instrument and invention are described. The instrument contains all components mentioned and contains an actuating system that lances and places the capillary at the lance site. Another embodiment describes the instrument first placing a test strip at the skin surface and then piercing the skin through the test strip with a lancet.
Another device by Douglas et al. U.S. Pat. No. 6,183,489 describes a macro collection device where the fluids are drawn up by a capillary tube to an external analytic test strip.
Another device described by Frederick L. Dechow, U.S. Pat. No. 4,883,068, refers to a blood sampling device and method. The instrument consists of a double-sided cannula and a reservoir with a penetrable end cap axially aligned in a compressible device. The device is laid upon the skin and compressed. This motion causes the cannula to first puncture the skin surface and then the reservoir end cap. In this position blood is then delivered to the reservoir.
The present invention is an integrated lancing and analytic device for collecting fluid from skin. The device has a lance and an analytic device integrated into a single device body. The lance and inlet of the analytic device are positioned in the device body so that the fluid released by the lance is taken up into the inlet by having the device body direct the lance and the analytic device to the fluid released from the skin. The device body is preferably plastic and is fabricated using plastic injection molding.
More specifically the invention comprises an integrated lancing and analytic device for collecting fluid from skin said device having a lance and an analytic device integrated into a single device body wherein: (i.) the lance has a tapered skin penetrating portion extendible from the body so that it penetrates the skin to release fluid when the body of the device is held to the skin; (ii.) the analytic device comprises an inlet, an analytic region having capillary dimensions, an outlet and a signal pathway wherein the analytic region is positioned in fluid communication between the inlet and outlet and the signal pathway transmits a signal of analysis from the analytic region to the outside, optionally the signal is not visible to a user; and (iii.) wherein the lance and inlet of the analytic device are positioned in the device body at an angle of less than 180 degrees so that the fluid released by the lance is taken up into the inlet by having the device body direct the inlet of the lance and the analytic device to approximately the same position thereby collecting the fluid released from the skin.
The lance is an object used to penetrate the skin, less than 2 mm in depth, preferably having the form of a needle. In one embodiment the lance may be rigidly attached to the device body, having a tapered skin-penetrating portion extending from the body. In this embodiment the lance may incorporate a fluid channel, internally such as in a hypodermic syringe, or on the surface. In another embodiment the lance is moveably positioned within a pathway within the body and has a tapered skin-penetrating portion that extends from the body. The lance may be spring loaded in the device body to provide a driving mechanism. The lance is slidably mounted and able to move along the pathway so that it penetrates the skin and retracts to release fluid from the skin when the body of the device is held to the skin. The lance may be fabricated from metal, silicon, or plastic.
The analytic device is used to pull body fluid off from the skin surface and perform an analysis on the fluid. The fluid may be blood, interstitial fluid, or a combination of both, having a volume range of 50-300 nanoliters. The analytic device comprises an inlet, an analytic region, an outlet and a signal pathway wherein the analytic region is positioned in fluid communication between the inlet and outlet and the signal pathway transmits a signal of analysis from the analytic region to the outside. The signal pathway may be either a pair of electrodes or an optical signal. The analytic device may be either held rigidly in the device body or moveably positioned (slidably mounted) within a pathway within the device body. When positioned moveably within the device body the analytic device may be spring loaded within the device body. In one embodiment the device body may create a fluid seal with the analytic device. The analytic device may be fabricated from either silicon, or a combination of silicon with plastic or glass.
One object of the present invention is to provide an instrument system comprising an instrument housing containing an integrated lancing and analytic device for collecting fluid from skin. The instrument housing is fitted to removably house the device having a lance and an analytic device integrated into a single device body. The lance has a tapered skin-penetrating portion which extends from the body so that it penetrates the skin and retracts to release fluid from the skin when the instrument housing is held to the skin; the analytic device comprises an inlet, an analytic region, an outlet and a signal pathway wherein the analytic region is positioned in fluid communication between the inlet and outlet and the signal pathway transmits a signal of analysis from the analytic region to the outside; and the lance and inlet of the analytic device are positioned in the device body so that the fluid released by the lance is taken up into the inlet without removing the instrument housing from the skin. Both the lance and the analytic device may be rigidly attached to the device body, moveable within the device body, spring loaded within the device body, spring loaded within the instrument housing, or driven by an electromechanical device within the instrument housing.
Another object of the present invention is to provide a method of collecting and analyzing fluids from skin. The method comprises four steps: (1) positioning on the skin of an animal an instrument housing containing a removable, integrated lancing and analytic device for collecting fluid from skin said device having a lance and an analytic device integrated into a single device body; (2) penetrating the lance into the skin to release fluid; (3) positioning the analytic device to the location on the skin penetrated by the lance; (4) analyzing the fluid that enters the analytic device through the inlet.
One variation of the method may allow for the lance to be reinserted into the skin while positioning the analytic device on the skin. Another variation of the method may allow for pivoting the device body to position the lance and analytic device on the skin. The fluid in the analytic device may be analyzed using several methods: optical, electrochemical, fluorescence, or chemiluminescence. The preferred analyte for the fluid is glucose.
Another object of the present invention is to provide a process for manufacturing an integrated lancing and analytic device for collecting fluid from skin, the device having a lance and an analytic device integrated into a single device body. The process comprises attaching a lance and analytic device to a device body wherein the lance and inlet of the analytic device are positioned in the device body so that fluid released by the lance is taken up into the inlet without having to remove the device from the skin. This is accomplished by directing the lance and the analytic device to the same position on the skin. By same position, it is meant that the inlet of the analytic device is positioned in adequate proximity to the fluid released by the lance to permit uptake of the fluid without the user having to remove the device from the skin and visibly reposition the inlet to the fluid. This would include a slight rocking motion of the device as in a pivoted configuration.
Unless otherwise stated, all physical variations of the devices described herein are applicable to the methods of manufacturing and methods of uses described herein.